package test;

import java.awt.BorderLayout;
import java.awt.Container;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.Insets;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.ComponentAdapter;
import java.awt.event.ComponentEvent;
import java.beans.PropertyVetoException;

import javax.swing.JButton;
import javax.swing.JDesktopPane;
import javax.swing.JFrame;
import javax.swing.JInternalFrame;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
import javax.swing.plaf.basic.BasicInternalFrameUI;

public class MDIFrame extends JFrame { 
	  
    /** The desktop pane. */ 
    final JDesktopPane desktopPane = new JDesktopPane(); 
  
    /** The operation pane with restore and close buttons. */ 
    final JPanel opPane = new JPanel(); 
  
    /** 
     * Instantiates a new mDI frame. 
     */ 
    public MDIFrame(){ 
      setTitle("MDI Frame"); 
      setSize(600, 550); 
      setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 
   
      final JMenuBar bar = new JMenuBar(); 
      JMenuItem exit = new JMenuItem("Exit"); 
          exit.addActionListener(new ActionListener(){ 

              @Override 
              public void actionPerformed(ActionEvent e) { 
                   System.exit(0); 
              } 
    
      }); 
      bar.add(exit); 
      // operation pane with two button, set invisible at first 
      opPane.setLayout(new FlowLayout(FlowLayout.TRAILING)); 
      JButton restore = new JButton("#"); 
      restore.setMargin(new Insets(0, 0, 0, 0)); 
      restore.setPreferredSize(new Dimension(15, 15)); 
      restore.addActionListener(new ActionListener(){ 

      @Override 
      public void actionPerformed(ActionEvent e) { 
            InnerFrame i = (InnerFrame)desktopPane.getSelectedFrame(); 
            try { 
                // notice this method, when JInternalFrame set maximun false
                // this internal frame will be set as old size 
                i.setMaximum(false); 
            } catch (PropertyVetoException ex) { 
                ex.printStackTrace(); 
            } 
            i.showNorthPanel(); 
            opPane.setVisible(false); 
          } 
    
      }); 
      opPane.add(restore); 
      JButton close = new JButton("X"); 
      close.setMargin(new Insets(0, 0, 0, 0)); 
      close.setPreferredSize(new Dimension(15, 15)); 
      close.addActionListener(new ActionListener(){ 

          @Override 
          public void actionPerformed(ActionEvent e) { 
            JInternalFrame i = desktopPane.getSelectedFrame(); 
            i.dispose(); 
            opPane.setVisible(false); 
          } 
    
      }); 
      opPane.add(close); 
      bar.add(opPane); 
      opPane.setVisible(false); 
      setJMenuBar(bar); 
   
      Container content = getContentPane(); 
      content.add(desktopPane, BorderLayout.CENTER); 
      final JPanel ctrlPane = new JPanel(); 
      JButton add = new JButton("add"); 
      add.addActionListener(new ActionListener(){ 

          @Override 
          public void actionPerformed(ActionEvent e) { 
              InnerFrame iFrame = new InnerFrame(); 
              iFrame.setVisible(true); 
              desktopPane.add(iFrame); 
          } 
    
      }); 
      ctrlPane.add(add); 
      content.add(ctrlPane, BorderLayout.SOUTH); 
      setVisible(true); 
    } 
  
    /** 
     * The Class InnerFrame. 
     */ 
    class InnerFrame extends JInternalFrame { 
   
      /** The is hidden. */ 
      boolean isHidden = false; 
   
      /** The old ui. */ 
      BasicInternalFrameUI oldUi = null; 
   
      /** 
       * Instantiates a new inner frame. 
       */ 
      public InnerFrame() { 
          oldUi = (BasicInternalFrameUI)getUI(); 
          setSize(200, 200); 
          maximizable = true; 
          closable = true; 
          addComponentListener(new ComponentAdapter() { 
              public void componentResized(ComponentEvent e) { 
                  InnerFrame selectedFrame = (InnerFrame)e.getSource(); 
                  if(selectedFrame.isMaximum()){ 
                      selectedFrame.hideNorthPanel(); 
                      opPane.setVisible(true); 
                      try { 
                           selectedFrame.setMaximum(true); 
                      } catch (PropertyVetoException ex) { 
                           ex.printStackTrace(); 
                       } 
                   } 
               } 
          }); 
      } 
   
      /** 
       * Hide north panel. 
       */ 
      public void hideNorthPanel(){ 
          ((BasicInternalFrameUI) this.getUI()).setNorthPane(null); 
          this.putClientProperty("JInternalFrame.isPalette", Boolean.TRUE); 
          isHidden = true; 
      } 
   
      /** 
       * Show north panel. 
       */ 
      public void showNorthPanel() { 
          this.setUI(oldUi); 
          this.putClientProperty("JInternalFrame.isPalette", Boolean.FALSE); 
          isHidden = false; 
      } 
   
      /* (non-Javadoc) 
       * @see javax.swing.JInternalFrame#updateUI() 
       */ 
      public void updateUI() { 
          super.updateUI(); 
          if (isHidden) { 
              hideNorthPanel(); 
          } 
       } 
    } 
  
    /** 
     * The main method. 
     *  
     * @param args the arguments 
     */ 
    public static void main(String[] args) { 
          SwingUtilities.invokeLater(new Runnable(){ 

              @Override 
              public void run() { 
                   new MDIFrame(); 
              } 
    
          }); 
     } 
} 

